A communication system can be seen as a facility that enables communication sessions between two or more entities such as fixed or mobile communication devices, base stations, servers and/or other communication nodes. A communication system and compatible communicating entities typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. For example, the standards, specifications and related protocols can define the manner how communication devices can access the communication system and how various aspects of communication shall be implemented between communicating devices. A communication can be carried on wired or wireless carriers. In a wireless communication system at least a part of the communication between at least two stations occurs over a wireless link.
Examples of wireless systems include public land mobile networks (PLMN) such as cellular networks, satellite based communication systems and different wireless local networks, for example wireless local area networks (WLAN). A wireless system can be divided into cells, and hence these are often referred to as cellular systems. A cell is provided by a base station. Cells can have different shapes and sizes. A cell can also be divided into sectors. Regardless of the shape and size of the cell providing access for a user equipment, and whether the access is provided via a sector of a cell or a cell, such area can be called radio service area or access area. Neighbouring radio service areas typically overlap, and thus a communication in an area can listen to more than one base station.
A user can access the communication system by means of an appropriate communication device. A communication device of a user is often referred to as user equipment (UE) or terminal. A communication device is provided with an appropriate signal receiving and transmitting arrangement for enabling communications with other parties. Typically a communication device is used for enabling receiving and transmission of communications such as speech and data. In wireless systems a communication device provides a transceiver station that can communicate with another communication device such as e.g. a base station of an access network and/or another user equipment. The communication device may access a carrier provided by a station, for example a base station, and transmit and/or receive communications on the carrier.
An example of communication systems attempting to satisfy the increased demands for capacity is an architecture that is being standardized by the 3rd Generation Partnership Project (3GPP). This system is often referred to as the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology. The LTE aims to achieve various improvements, for example reduced latency, higher user data rates, improved system capacity and coverage, reduced cost for the operator and so on. A further development of the LTE is often referred to as LTE-Advanced. The various development stages of the 3GPP LTE specifications are referred to as releases.
One aspect of LTE is that a Multimedia Broadcast/Multicast Service (MBMS) for a Universal Mobile Telecommunications System (UMTS) can be provided. The MBMS uses broadcast or multicast message distribution instead of several point-to-point links for communicating to several end user equipments.
A UE that operates in a UMTS or LTE network can obtain communication services using procedures according to a standard defined by the 3GPP. The standard specifies, for both of these networks, radio system parameters, data transfer procedures, network protocols, control messages and bearer traffic exchange to take place over the air interface. The MBMS can allow efficient session management by enabling service data packets to be transferred in an efficient way to multiple UEs within these networks. For this purpose, a message can be transmitted from a core network node to several node Bs (nBs). Each NB can then send a unidirectional point-to-multipoint (PtM) transmission to UEs so that a UE in an idle or active mode receives network service data.
In a multicarrier environment an MBMS broadcast/multicast may be configured for a certain cell layer to provide efficient radio resource usage for the MBMS broadcast/multicast.
Long term evolution (LTE) release 9 (LTE Rel-9) standards included a basic MBMS functionality of pure broadcast mode transmission with no uplink feedback loop of any form. However in order that the control entity supporting multimedia broadcast multicast service (MBMS) can allocate resources efficiently, information regarding the user equipment receiving the broadcast is typically gathered.
The control information relevant for user equipment supporting MBMS is generally separated as much as possible from unicast control information. Standard releases such as release 10 (LTE Rel-10) have specified feedback in terms of counting to aid the operators decision making on what services to broadcast. In other words the user equipment can indicate whether or not they are interested in receiving these services indicated in the counting request.
The counting response RRC message defined in LTE Rel-10 contains only references to the contents of the counting request to which it is addressed. However there may be problems in a multicarrier scenario where a user equipment sends a counting response message to a cell different to that broadcasting the counting request. This response thus can lead to problems of determining to what exactly the response refers to. In the worst case scenario the network associates the counting responses to the wrong counting procedure making the results erroneous.
Whilst it has been generally agreed that the user equipment can send counting responses to a serving cell regardless of the relationship to the cell broadcasting the counting request, typically it is assumed that coordination on the network side ensures at any given location no two counting procedures are carried out at the same time.
However should the user equipment receive a counting request from another public land mobile network (PLMN), in other words a network operated by a different operator from that serving the user equipment, the user equipment should not respond to the request (as the two separate networks cannot be guaranteed to not be operating counts at the same time). Coordination between the two networks in such an example to avoid two counting procedures being carried out at the same time at any location furthermore is typically difficult to achieve across different public land mobile networks.
There is an additional problem associated with the scenario shortly following an inter-PLMN handover to a cell which is no longer broadcasting the identity of the user equipment registered PLMN. In such an example the user equipment can receive or discover a counting request being broadcast on a cell of a frequency carrier where the user equipment is receiving MBMS and still answer the counting request procedure incorrectly as the access stratum of the user equipment still considers the registered public land mobile network (RPLMN) to be the one used in the previous cell. In the converse case for the same reasons, a user equipment may also not respond to an observed counting request even though the PLMN identity broadcast by the target cell of the handover would actually warrant it.
If the new cell broadcasts the PLMN identity of the RPLMN, then the RPLMN can stay the same and there is no need to do anything. However, in the case of interest where the new cell does not broadcast the identity of the RPLMN then a tracking area update (TAU) is required and the RPLMN value will change in the procedure.
Thus the problem is that the access stratum of the user equipment will determine whether or not to answer to a counting request without checking whether or not the RPLMN is still valid in the current serving cell.
Statement of Application
Embodiments of the application aim to address one or several of the above issues.
According to an aspect of the application there is provided a method comprising: receiving a first message at a user equipment from a first apparatus; receiving from a primary access node at least one network identifier value; comparing a user equipment registered network identifier value to the at least one network identifier value from the primary access node; and responding to the first message dependent on the user equipment registered network identifier value being equal to any primary access node network identifier value.
The method may further comprise: receiving from the first apparatus at least one network identifier value; comparing the at least one network identifier value from the first apparatus to a user equipment registered network identifier value; wherein responding to the first message is further dependent on any network identifier value from the first apparatus being equal to the user equipment registered network identifier value.
The method may further comprise determining the user equipment registered network identifier.
The user equipment registered network identifier value may comprise the registered public land mobile network identifier.
The method may further comprise: performing a tracking area update for the user equipment when the user equipment registered network identifier value is different from every primary access node network identifier value; updating the user equipment registered network identifier value; comparing the updated user equipment registered network identifier value to the at least one network identifier value from the first apparatus; and responding to the first message dependent on the updated user equipment registered network identifier value being equal to one of the network identifier values from the first apparatus.
The first message may be a Multimedia Broadcast-Multicast Service ‘MBMSCountingRequest’ message.
Responding to the first message may comprise: generating a Multimedia Broadcast-Multicast Service ‘MBMSCountingResponse’ message; and transmitting the Multimedia Broadcast-Multicast Service ‘MBMSCountingResponse’ message to an access node.
The first apparatus may comprise at least one of: a base station within a network with the network identifier value; and an enhanced NodeB (eNB) broadcasting a multimedia broadcast-multicast services control channel (MCCH).
The primary access node may comprise at least one of: a primary cell serving the user equipment; and a primary cell enhanced NodeB.
The method may further comprise: monitoring at least one control channel from the first apparatus wherein the at least one control channel comprises the first message.
The network identifier value may be a public land mobile network identifier value.
The user equipment registered network identifier value may comprise the registered public land mobile network identifier value.
The at least one network identifier value may be received in a system information broadcast message.
The primary access node may be the first apparatus.
According to a second aspect of the application there is provided apparatus comprising: means for receiving a first message at a user equipment from a second apparatus; means for receiving from a primary access node at least one network identifier value; means for comparing an apparatus registered network identifier value to the at least one network identifier value from the primary access node; and means for responding to the first message dependent on the apparatus registered network identifier value being equal to any primary access node network identifier value.
The apparatus may further comprise: means for receiving from the second apparatus at least one network identifier value; and means for comparing the at least one network identifier value from the second apparatus to the apparatus registered network identifier value; wherein the means for responding to the first message is further dependent on any network identifier value from the second apparatus being equal to the apparatus registered network identifier value.
The apparatus may further comprise means for determining the apparatus registered network identifier.
The apparatus registered network identifier value may comprise the registered public land mobile network identifier.
The apparatus may further comprise: means for performing a tracking area update for the apparatus when the apparatus registered network identifier value is different from every primary access node network identifier value; means for updating the apparatus registered network identifier value; means for comparing the updated apparatus registered network identifier value to the at least one network identifier value from the second apparatus; and means for responding to the first message dependent on the updated apparatus registered network identifier value being equal to one network identifier values from the second apparatus.
The first message may be a Multimedia Broadcast-Multicast Service ‘MBMSCountingRequest’ message.
The means for responding to the first message may comprise: means for generating a Multimedia Broadcast-Multicast Service ‘MBMSCountingResponse’ message; and means for transmitting the Multimedia Broadcast-Multicast Service ‘MBMSCountingResponse’ message to an access node.
The apparatus may be a user equipment.
The second apparatus may comprise at least one of: a base station within a network with the network identifier value; and an enhanced NodeB (eNB) broadcasting a multimedia broadcast-multicast services control channel (MCCH).
The primary access node may comprise at least one of: a primary cell serving the apparatus; and a primary cell enhanced NodeB.
The apparatus may further comprise: means for monitoring at least one control channel from the second apparatus wherein the at least one control channel comprises the first message.
The network identifier value may be a public land mobile network identifier value.
The apparatus registered network identifier value may comprise the registered public land mobile network identifier value.
The at least one network identifier value may be received in a system information broadcast message.
The primary access node may be the second apparatus.
According to a third aspect of the application there is provided an apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and computer program code configured, with the at least one processor, to cause the apparatus to perform: receiving a first message at a user equipment from a second apparatus; receiving from a primary access node at least one network identifier value; comparing an apparatus registered network identifier value to the at least one network identifier value from the primary access node; and responding to the first message dependent on the apparatus registered network identifier value being equal to any primary access node network identifier value.
The apparatus may be further caused to perform: receiving from the second apparatus at least one network identifier value; and comparing the at least one network identifier value from the second apparatus to the apparatus registered network identifier value; wherein responding to the first message is further dependent on any network identifier value from the second apparatus being equal to the apparatus registered network identifier value.
The apparatus may be further caused to perform determining the apparatus registered network identifier.
The apparatus registered network identifier value may comprise the registered public land mobile network identifier.
The apparatus may be further caused to perform: a tracking area update for the apparatus when the apparatus registered network identifier value is different from every primary access node network identifier value; updating the apparatus registered network identifier value; comparing the updated apparatus registered network identifier value to the at least one network identifier value from the second apparatus; and responding to the first message dependent on the updated apparatus registered network identifier value being equal to one network identifier values from the second apparatus.
The first message may be a Multimedia Broadcast-Multicast Service ‘MBMSCountingRequest’ message.
Responding to the first message may further cause the apparatus to perform: generating a Multimedia Broadcast-Multicast Service ‘MBMSCountingResponse’ message; and transmitting the Multimedia Broadcast-Multicast Service ‘MBMSCountingResponse’ message to an access node.
The apparatus may be a user equipment.
The second apparatus may comprise at least one of: a base station within a network with the network identifier value; and an enhanced NodeB (eNB) broadcasting a multimedia broadcast-multicast services control channel (MCCH).
The primary access node may comprise at least one of: a primary cell serving the apparatus; and a primary cell enhanced NodeB.
The apparatus may be further caused to perform monitoring at least one control channel from the second apparatus wherein the at least one control channel comprises the first message.
The network identifier value may be a public land mobile network identifier value.
The apparatus registered network identifier value may comprise the registered public land mobile network identifier value.
The at least one network identifier value may receive in a system information broadcast message.
The primary access node may be the second apparatus.
A computer program comprising computer executable instructions which when run on one or more processors may perform the method as described herein.
It should be appreciated that any feature of any aspect may be combined with any other feature of any other aspect.